Silent chain drive



June 30, 1931. H. E. HAYWARD I SILENT CHAIN DRIVE Filed April 5. 1929 2 Sheets-Sheet 1 J a HMMWW w; m 7% L| j 6 n; 6 y; 6. Z 1 9w 5 1 J 7W 0 w f hi I y f %u fi fi d June 30, 1931. H. E. HAYWARD 1,812,095

' SILENT CHAIN DRIVE Filed April 5. 1 929 2 Sheets- Sheet 2 Patented June 3 0, 1931;

* N ED HENRY, E. AYWARD, or INDIAl\TAPO IJIIS, I'NDiANA, Assienon 'To LINK-Brim PANY, on cHIcAGo, Lnnvois, Acon-roimfrion or ILLIN OISf v srL'nN'r. 01mm R E- l Application mea'i ri t, 1929; i Serial no. 352,677,-

My invention relates to improvements in silent chain drives and has for one object to provide a new and improved type of silent chain drive wherein the chain maybe placed on and removed from the sprockets- Without disconnecting the ends of the chain an'd without laterally displacing any of the chain sprockets.

. 1 Silent chain is ordinarily held on the chain sprocket against displacement in a direction parallel with the'axes' of the Sprockets by providing in one instance What are "called guide links,- that is; links having 'flangesex tending, inwardlyto a point" between the center of rotation andfthe-end-of the tooth. 7 Sometimes the tooth sprocket is cut away p or grooved to'engageithese flanges when the I flanges are located between the'sides of the chain. other. instances these flanges are located at the outer sides of the chain'and extend down along side the ends oflthe teeth.

inwhich case thegteethfare continuous but terminate short of the ontsideredge of the chain; Heretofore'it'has been thought that these -flanges must be substantially conti nnousand ordinary p'ractice has been to have the flanges :on every other link. Whenthis is the case, ,silent'chain can be mounted on" the sprockets only .intwo ways either by disconnecting the ends of thechain for as-- sembly and then "joiningthe en'ds' after the chain is in placeor by mounting one or more of the sprockets in'such Wayjthat it maybe moved transversely to permit the "chain to be put infplace and thenimovedbackto bring the chain r n; a

Ihave discovered that it is only necessary i and sprockets into proper "to have "a comparatively vsmall number of these guide links Perhaps. only one or two even inan entire chain butiin any event in order to' accomplish the assembly. it; is only necessary to cut awayfenou'gh of these'guide, links to'exceedthe arc of engagement of the chain with one of the Wheels of the drive;v

VVhen-this is'done" the chain is placed on one :or more of the Wheels in such position that that portion of the chain vvhere the guide flanges are omitted comes; in register/With one of the sprockets; When this is done,v

the chain can be moved laterally'onto the position: hen" experience shows that as sprocket until it resumes its proper working the chainis driventhe remaining guide" links 1 engaging the sprockets are suflicient to keep thechain in line b'ecase'a'llbut a very slight; -moveinent-of thec hainin adirection parallel to the rotationof the sprockets is. prevented by the remaining guide flangesandesincethe g of the entire chain ontoall the sprockets at once. In this-casethe guide links wouldibe 70, foundwhenthechainwasinlassembly posi tion only in the lengths of chain betweentlie arcs of contact'with all of the sprockets. In order] to-assist' in the operation of asvsei'nbling the ,chainI may, if desired, providei onefor more blank 'mandrels which Will drel with respect'to the sprocketsso that each 7 individual linkis .held, and "guided by the vmandrel as it is laterally displaced ;in'to workingposition :on the sprocket. This'i's not essential bnt in some instances makes the. I

assembly a 'simpler'and easier matter.

p in" the Q; accompanying dra W1ngs,,Where'1n, i

Figure .l' isfa: side elevation Qf-Et chain drive;

be engaged by the. ends of the-chain teeth f and may beplaced in juxtaposition with or against the face of the 5 sprocketsxi'f desired V'II QGaIIS being provided for properly, adjust-* Ting the chainon the mandreland the man- Myinvention is illustrated 111016 orfless diagrammatically "Figureflis'laplan view of the chain drive as "the drive is; aboutz to be, assembled sho'w ingv the chain in position on two oft the, z sprockets;

'FlgllI'G 3 1s similar plan showing 1 the'chain about to be placedon thesprockets whenutlie chain isassembled by moving the e entire;chain laterally;; a

Figure at shows a section through the chain with central guide links;

Figure 5 shows a section through the chain with side guide links;

Figure 6 is a diagrammatic view showing chain side links omitted for only one arc of contact;

Figure 7 is a diagrammatic view showing chain side links omitted for the arc of contact with all the sprockets;

Figure 8 shows but a single guide link.

Like parts are indicated by like characters throughout the specifications and drawings.

A is a driving sprocket. A A are driven sprockets. These sprockets are permanently mounted respectively on the shafts A" A A. A are grooves cut in the peripheries of all the sprockets where the teeth are cut away to make a place for the guide links.

The silent chain controls all the sprockets. It is made up of a series of interlocking toothed links B B joined together end over lapping end in alternate relation by the pivot pins B The teeth of the inks straddle the teeth B of the sprocket. Placed centrally along the length of the chain are a series of guide links B which links are not toothed but extend down toward the axis of rotation of the sprocket a distance substantially equal though it may be greater than or less than the depth of the chain tooth. These guide sprockets travel in the grooves in the peripheries of the gears and may be in engagement with the ends of the teeth to guide and center the chain and prevent it from moving laterally in a direction paral- 101 with the axis of rotation of the gears. It these guide links which ordinarily are so placed that they are associated with every alternate group of toothed links. It will be noted. that in my invention I have shown the guide links omitted for a distance greater than the arc of contact between the chain and the smaller of the three sprockets so that as in Figure 2 the :chain may be put in place engaging the two larger sprockets brought up against the face 01 the smaller sprocket and moved transversely into position thereon.

C is the mandrel having a smooth cylindrical surface of such size as when the teeth of the chain engage it theteeth are held in proper pitch relatiom'that is, in the same general relation that they are to be held in position on the sprocket so that they can be easily slid into relation with the sprocket without binding. This mandrel rides on the face of the sprocket, being centered thereon by the end of the shaft which carries thesprocket as indicated.

In the modified form, it is noted that there are a plurality of mandrels C C of a size corresponding to the position of tire chain on the other two pinions or gears when assembled so that as indicated when the guide flanges are omitted to correspond with the arc of contact of all three of the sprockets, the chain may be bodily moved into register with the sprockets off the mandrels, the mandrcls being then removed leaving the chain free to operate.

In the diagrammatic figures I have shown my invention as applied in different manners as under varying conditions a greater or lesser number of the guide links may be omitted and in the extreme case where but a single guide link is used experience has shown that for many purposes this one guide link is abundantly sufiicient as the chain operates to maintain the chain in proper position on the sprockets.

I claim:

1. In a silent chain drive, a plurality of toothed peripherally grooved sprockets and a chain comprising a plurality of articulated toothed links in mesh with the sprocke teeth, means for preventing transverse movement of the chain comprising a single guise link, adapted to penetrate the sprocket and engage the ends of the sprocketteeth forming the sides of the groove.

2. In a silent chain drive, a plurality of toothed peripherally grooved sprockets and a chain comprising plurality of articulated toothed lin s in mesh with the sprocket teeth, means for preventing transverse movement of the chain comprising guide links adapted to penetrate the sprocket and engage the ends of the sprocket teeth forming the sides of the groove, the guide links being omitted for a distance along the chain exceeding the are of contact between the chain and one of the sprockets.

3. In a silent chain drive, a plurality of toothed peripherally grooved sprockets and a chain comprising a plurality of articulated toothed links in mesh with the sprocket teeth, means for preventing transverse movement of the chain comprising guide links adapted to penetrate the sprocket and ongage the ends of tho sprocket teeth forming the, sides of the groove, the guide links being omitted along the chain at a plurality of places therealong in each case for a distance exceeding the arc of contact between the chain andeach one of the sprockets.

4. In a silent chain drive, a plurality of toothed sprockets and a chain comprising a plurality of articulated toothed links in mesh with the sprocket teeth, means for preventing transverse movement of the chain comprising guide links adapted to engage the sprocket teeth the links being omitted for a distance along the chain greaterthan the arc of contact with one of the sprockets.

5. In a silent chain drive, a plurality of toothed sprockets and a chain comprising a plurality of articulated toothed links in mesh with the sprocket teeth, means for ventin transverse movement of the chain 1:

- toothed sprockets and a chain comprising a'plurality of articulated toothed links in- I position and length to the arc of contact becomprising guide links adapted 'to engage the ends of the sprocket teeth, the links, be-

ing omitted for a distance along the chain greater than the arc'of contact with one of the sprockets, there. being a plurality ,of places along thechain where the guide links are omitted, such'places corresponding in tween the chain and each vof'the sprockets. 6. In a silent chain drive, a plurality or meslrwith the sprocket teeth, means carried by the chain adapted to engage the ends of by the chain adapted to engage the sprocket teeth for preventingtrans verse movement of the chain thereon,sa1d means-b'elng om tted i through a lengthon thefchain greater than v the arc of contact between the chain and one of the sprockets, there-being a plurality of areas on thechain where such means, are omitted conforming to "the position and angle of contact of each of the sprocket-s.

'8; In a'silent chain drive, a plurality of" toothed sprockets and a chaincomprising a plurality of articulated toothedlinksin mesh with the sprocket teeth, vmeans carried by- I the chain adapted to engage the ends of the sprocket teeth for preventing transverse movement of the chain thereon, saidflmeans being omitted through alength on the chain chain and, one ofthe sprockets, and a mandrel in removable engagement with the are conforming tothelposition of the teeth I on the sprocket to permit lateral displacement of the chain from the mandrel into position on the sprocket.

10. In combinationfwlth a silent drive chain comprising a plurality of toothed" sprockets and a chain made up of a plurality of articulated toothed links-Lin mesh with the sprocket teeth, meansv for preventing transverse movement of the chain comprising 3 guide links adapted to engage. the ends.v of

the sprocket teeth,"said links beingomitted tolpermit transverse movement of the chain on the sprocket'for the purpose of assembly,

amandrel adapted to be associated with a sprocket to engage the ends of the chain teeth to hold them in normal position away from the center of rotation ofthesprocket to permit, their transverse movement into register with the teeth,

' '11. In a silent chain drive, a piumut or I toothed sprockets, an endless chain comprising "a plurality of articulated toothed.

links in mesh with the sprocket teeth,means for preventing transverse movement ofthe chain and aligning it on the sprocket teeth v comprising means associated with a singlev pitch ofthe chain only'adapted to engage successive sprockets, as thechain travels and to'as such successive engagements take place align the chain on the sprocket at the point wherefsuch singlemeansengages it.

, Signed at Indianapolis, county of Marion,

March,

' greaterthan the arc of contact between the v sprocket adapted to engage the chain teeth and support them inan arc'conforming to a the position of the teeth'on the sprocket to from the mandrel into position Jon the sprocket. e

' 9. In a silent chain drive,a p1urality of permit lateral displacement ,of the chain f toothed sprockets and a chain comprising a.

plurality ofsarticulated toothed links in mesh with the sprocket teeth, means carried by the p chain adaptedto engage the ends, of-the sprocket teeth for, preventing "transverse movement of the chain thereon, said means being omitted through a lengthion' theichain greater thanthe arcof contactbetween the chain and one of'the sprockets, therebeing I 1 a plurality of areas onthechain wheresuch: 1 means are omitted conforming to the-position and angle of contact of each of the sprockets, and amandrel in removableengagement with the sprocket adapted to ens gage the chain teeth and support them in an I and State of Indiana, this 30thi'day of,

* rIE 'RY HAY ARD. I 

